clear-pkgs-linux-iot-lts2018/0571-Kernel-Acrn-Use-HYPERVISOR_CALLBACK_VECTOR-for-Acrn-.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Zhao Yakui <yakui.zhao@intel.com>
Date: Tue, 16 Oct 2018 13:38:18 +0800
Subject: [PATCH] Kernel/Acrn: Use HYPERVISOR_CALLBACK_VECTOR for Acrn upcall
 vector

Linux kernel uses the HYPERVISOR_CALLBACK_VECTOR for hypervisor upcall vector.
And it is already used for Xen and HyperV.
After Acrn hypervisor is detected, it will also use this defined vector as notify
vector to kernel.

Tracked-on: https://github.com/projectacrn/acrn-hypervisor/issues/1325
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
---
 arch/x86/acrn/acrn.c             | 40 ++++++++++++++++++++++++++++++++
 arch/x86/entry/entry_64.S        |  5 ++++
 arch/x86/include/asm/acrnhyper.h | 18 ++++++++++++++
 arch/x86/include/asm/hardirq.h   |  2 +-
 arch/x86/kernel/irq.c            |  2 +-
 5 files changed, 65 insertions(+), 2 deletions(-)
 create mode 100644 arch/x86/include/asm/acrnhyper.h

diff --git a/arch/x86/acrn/acrn.c b/arch/x86/acrn/acrn.c
index eea9db8..12ebc4f 100644
--- a/arch/x86/acrn/acrn.c
+++ b/arch/x86/acrn/acrn.c
@@ -34,6 +34,10 @@
  */
 #include <asm/hypervisor.h>
 #include <linux/vhm/vhm_msi.h>
+#include <asm/acrnhyper.h>
+#include <asm/irq_vectors.h>
+#include <asm/irq_regs.h>
+#include <asm/desc.h>
 
 static uint32_t __init acrn_detect(void)
 {
@@ -45,6 +49,9 @@ static void __init acrn_init_platform(void)
 #if  defined(CONFIG_PCI_MSI) && defined(CONFIG_ACRN_VHM)
 	pv_irq_ops.write_msi = acrn_write_msi_msg;
 #endif
+
+	alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR,
+                                acrn_hv_callback_vector);
 }
 
 static void acrn_pin_vcpu(int cpu)
@@ -63,6 +70,37 @@ static void __init acrn_init_mem_mapping(void)
 	/* do nothing here now */
 }
 
+
+static void (*acrn_intr_handler)(void);
+/*
+ * Handler for ACRN_HV_CALLBACK.
+ */
+__visible void acrn_hv_vector_handler(struct pt_regs *regs)
+{
+	struct pt_regs *old_regs = set_irq_regs(regs);
+
+	entering_ack_irq();
+#ifdef CONFIG_X86
+	inc_irq_stat(irq_hv_callback_count);
+#endif
+
+	if (acrn_intr_handler)
+		acrn_intr_handler();
+
+	exiting_irq();
+	set_irq_regs(old_regs);
+}
+
+void acrn_setup_intr_irq(void (*handler)(void))
+{
+	acrn_intr_handler = handler;
+}
+
+void acrn_remove_intr_irq(void)
+{
+	acrn_intr_handler = NULL;
+}
+
 const struct hypervisor_x86 x86_hyper_acrn = {
 	.name                   = "ACRN",
 	.detect                 = acrn_detect,
@@ -73,3 +111,5 @@ const struct hypervisor_x86 x86_hyper_acrn = {
 	.init.init_mem_mapping	= acrn_init_mem_mapping,
 };
 EXPORT_SYMBOL(x86_hyper_acrn);
+EXPORT_SYMBOL(acrn_setup_intr_irq);
+EXPORT_SYMBOL(acrn_remove_intr_irq);
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 617df50..d2305aa 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -1151,6 +1151,11 @@ apicinterrupt3 HYPERV_STIMER0_VECTOR \
 	hv_stimer0_callback_vector hv_stimer0_vector_handler
 #endif /* CONFIG_HYPERV */
 
+#if IS_ENABLED(CONFIG_ACRN)
+apicinterrupt3 HYPERVISOR_CALLBACK_VECTOR \
+	acrn_hv_callback_vector acrn_hv_vector_handler
+#endif
+
 idtentry debug			do_debug		has_error_code=0	paranoid=1 shift_ist=DEBUG_STACK
 idtentry int3			do_int3			has_error_code=0
 idtentry stack_segment		do_stack_segment	has_error_code=1
diff --git a/arch/x86/include/asm/acrnhyper.h b/arch/x86/include/asm/acrnhyper.h
new file mode 100644
index 0000000..1cfdb24
--- /dev/null
+++ b/arch/x86/include/asm/acrnhyper.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_ACRNHYPER_H
+#define _ASM_X86_ACRNHYPER_H
+
+#include <linux/types.h>
+#include <linux/atomic.h>
+#include <linux/nmi.h>
+#include <asm/io.h>
+
+#ifdef CONFIG_ACRN
+/* ACRN Hypervisor callback */
+void acrn_hv_callback_vector(void);
+
+void acrn_setup_intr_irq(void (*handler)(void));
+void acrn_remove_intr_irq(void);
+#endif
+
+#endif
diff --git a/arch/x86/include/asm/hardirq.h b/arch/x86/include/asm/hardirq.h
index d9069bb..5aa52d2 100644
--- a/arch/x86/include/asm/hardirq.h
+++ b/arch/x86/include/asm/hardirq.h
@@ -37,7 +37,7 @@ typedef struct {
 #ifdef CONFIG_X86_MCE_AMD
 	unsigned int irq_deferred_error_count;
 #endif
-#if IS_ENABLED(CONFIG_HYPERV) || defined(CONFIG_XEN)
+#if IS_ENABLED(CONFIG_HYPERV) || defined(CONFIG_XEN) || defined(CONFIG_ACRN)
 	unsigned int irq_hv_callback_count;
 #endif
 #if IS_ENABLED(CONFIG_HYPERV)
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index 59b5f2e..6b3eaab 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -134,7 +134,7 @@ int arch_show_interrupts(struct seq_file *p, int prec)
 		seq_printf(p, "%10u ", per_cpu(mce_poll_count, j));
 	seq_puts(p, "  Machine check polls\n");
 #endif
-#if IS_ENABLED(CONFIG_HYPERV) || defined(CONFIG_XEN)
+#if IS_ENABLED(CONFIG_HYPERV) || defined(CONFIG_XEN) || defined(CONFIG_ACRN)
 	if (test_bit(HYPERVISOR_CALLBACK_VECTOR, system_vectors)) {
 		seq_printf(p, "%*s: ", prec, "HYP");
 		for_each_online_cpu(j)
-- 
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